Story content courtesy of U.S. Department of Energy’s Brookhaven National Laboratory, US

Physicists working at the Department of Energy’s (DOE) Brookhaven National Laboratory and Switzerland’s Paul Scherrer Institute have revealed key quantum characteristics of high-temperature superconductors, demonstrating new experimental methods and breaking fundamental ground on these mysterious materials. Using a technique called resonant inelastic x-ray scattering (RIXS), scientists examined the magnetic spins of atomically thin layers of copper oxide materials. Researchers found that the spin waves present in complete, three-dimensional samples survived all the way down to the atomic level.

“For the first time, we can study truly two-dimensional behavior without the complicated interactions found on larger materials,” said Brookhaven physicist Mark Dean. “It’s widely believed that the essential electron pairing in high-temperature superconductors is magnetically mediated. Examining the fundamental building blocks of these superconductors, layers of copper and oxygen atoms, is key to understanding that magnetism and one day designing superconductors with even better properties.”

The full story behind high-temperature superconductivity remains uncertain, but this technique revealed that these quantum spins behave very similarly to classical magnets. The researchers, along with collaborators at University College London, UK, the Leibniz-Institut für Festkörper in Dresden, Germany, and Ecole Polytechnique Fédérale de Lausanne, Switzerland, also found that certain predicted quantum effects were not present in the two dimensional samples.

The research was funded through Brookhaven Lab’s Center for Emergent Superconductivity, an Energy Frontier Research Center funded by the U.S. Department of Energy’s Office of Science to seek understanding of the underlying nature of superconductivity in complex materials.